Resistance-grid.



N. WILKINSON.

' RESISTANCE GRID. APPLICATION rum) MAY 20, 1909.-

Patented Jan 4, 1910.

have become excessively neated. and thereby UNITED STATES PATENT OFFICE.

NATHAN WILKINSON, OF MILWAUKEE, WISCONSIN, ASSIGNOR TO ALLIS-CI-IALMERS COMPANY, A CORPORATION; OF NEW JERSEY.

RESISTANCE-GRID.

Specification of Letters Patent.

Patented Jan. 4, 1910.

Application filed May 20, 1909. Serial No. 497.3(29.

To all whom 'it may concern:

Be it known that I, NATHAN \Vnnnxsox, a citizen of the United States, residing at Milwaukee, in the county of Milwaukee and State of \Visconsin, have invented certain new and useful Improvements in Resistance- Grids, of which the following is a full, clear, and exact specification.

My invention relates to the construction of resistances for use in electric circuits.

Among the objects of my invention are, to obtain strength, durability, compactness, and chcapness of construction.

In addition to providing a resistance possessing superior structural features, the arrangement of the parts are such that they may all be readily assembled and firmly held in a permanent or fixed position, except those parts iptentionally made movable. In this construction, grids are so formed and assembled that one or more of the grids comprising the resistance, can be taken out and replaced in case of breakage or injury without much trouble.

Conspicuous among the features of improvement is a method of reii'iforcing or stiilening the grids, especially when they rendered flexible.

Figure 1 is a side view of one of the grids embodying my invention, parts being broken away and shown in section; and Figs. 2 and 3 are end and top views respectively oi the grid shown in Fig. 1.

llcb'lhtillltifi grids have been made very heavy and bulky in structure in order to withstand ars and tendencies to warp out of shape when excessively heated. The resistance grids shown in these drawings are made light in structure. These grids are made of suitable resistance material in zig Zag form, for example, substantially as shown in Fig. 1, so as to reduce into comparatively small space a resistance of considerable length.

The resistance grid consists of a conductor 10, formed substantially as shown and having its elements, such as 11 and 12, parallel and in integral connection to form a number of end-turns, such as 13 and 14, the conductor terminating in enlarged ends 15 formed of hooks or holes open on one side. These ends fit over insulated cross-rods or bolts of the suspending frame. The number of grids may Vary according to the desired length of the suspending frame. The end turns of the conductors, such as 13, 14, and 17, are provided With slots 18 to provide for the reception of insulating reinforcing but.- tons 19. These insulating buttons or members are set in the slots by springing apart the elements of the resistance grid. \Vhen all of the insulating members are set in place the enlarged portions of each of said members are in contact with the enlarged portions of the adjacent insulating members, thus forming a substantially stitt reinforcing means. The same reinforcing or stitfening arrangement is used at both top and bottom of the grid. sible to use grids which are comparatively frail in structure Withouthaving its elements warp to such an extent 'When excessively heated as to buckle up or come in contact with or to have adjacent grids in the same frame come in contact with each other.

It is evident that many modifications of the precise arrangement here shown may be made, and I aim in my claims to cover all such modifications which do not depart from the spirit and scope of my invention.

What I claim as new is:

v1. A resistance grid comprising a conductor having cud turns provided with slots, and insulating members occupying said slots for reinforcing said grid.

ii resistance grid comprising a conductor having end turns provided with slots in the sides of said and turns, and insulating members occupying said slots for reinforcing said grid.

, 3. ii resistance grid comprising a coin duclor having end turns provided with slots, and insulating members each one of which occupies two of said slots for reinforcing said grid.

41. A resist ance grid comprising a conductor having end turns provided with slots, said slots occurring in adjacent. sides of adjacent cud turns, insulating members occu pying said slots for reinforcing said grids.

5. A resistance grid comprising av couductor having end turns provided with slots, insulating members occupying said slots, enlarged portions of each of said insulating members in contact with the enlarged portions of each adjacent insulating member to form a. slili' reinforcing means.

6. A resistance grid comprising a conductor having cud turns provided with slots, insulating members occupying said slot for By means of this reinforcing it is posnn :1 condncrein'fm' 1 'iii.

5 resistance id comprising :1 conducttn' inn in; ant -'..n!ns PL'OVltl-Ni with slots tftt'i! of 1 iii? and turns having (me or innit: ato ls ain t ii'isniiiting members mitt siot's; for i'cinfmfcing said it). resistance grid comp h nundnctm iizivin and turns provided with sluts, said cnndnciimf including Pfll'zliiti elements, and insulating lneinbcis nijrunp ying suit slots to. reinibming said grid.

ll. The (:mi'ibinntiiin of it P' ist'zinco gi'it t COZIQ'NiSiTlg 2i conc tuctm iniv, 12; unit 7 turns PJ'OYAiQLi .iitil slots, and insuiiitiing nwmim's in the pi'osi-nt'o otf trvm Within a.

provided 11;; its t me .15; instituting 

